Spark plug



E. T. MARTIN July 29. 1924. 1,502,960

SPQRK PLUG Filed April 1, 1922 INTAKE v I 1 t1"; jffjjjli Patented July 29, 1924.

UNETE SPARK PLUG.

Application filed April 1, 1922. Serial No. 5483M.

To all whom it may concern:

. Be it known that I, EARL T. MARTIN, a

citizen of the United States, residing at Proctor, in the county of St. Louis and State of Minnesota, have invented certain new and useful Improvements inv Spark Plugs, of which the following is a specification, reference being had therein to the accompanying drawing. i

This invention relates to spark plugs for internal combustion engines, the principal object of which is to produce a self cleaning plu of this character.

(llher objects and advantages of the in vention will appear in the further description thereof.

In the accompanying drawing forming part of this application in which like ref erence characters indicate like parts:

Figure 1 represents a broken side elevation of a plug and its approximate relative position to a piston and exhaust portion of a cylinder;

Figure 2 is a top plan View of the plu and Figure 3 is a side elevation of the sparking points of the plug.

The plug in general may be of any standard make having prdvision for an axial electric terminal and a circumferential terminal, these two latter being changed and their modification embodying my present invention.

The axial terminal 1 is preferably reduced somewhat in size and offset slightly, as at 2, and made to extend considerably below the plug. At the offset portion of the terminal 1 is securely attached as at a the upper end of a thin resilient spring member 5 which depends parallel with the extension 6 of the terminal 1. The lower end of the resilient member 5 is broadened as at 7 into, somewhat spade like shape, preferably approximately the width of the sleeve of the plug and which normally rests against the slightly turned end 8 of the extension 6 of the terminal 1. This spade. or pallet like extension of the resilient member is provided at its lower extremity and upon the side opposite to the extension 6 with a step or log 9 rigidly fixed thereto.

The other terminal of the spark plug, which is indicated at 10, is rigidly fixed as at 11 in the usual manner to the circumferential terminal of the plug sleeve 3, is bent inwardly and againparallel with the axis of the plug, as at'12, where it is spaced the proper distance from the face of the pallet 7 to produce the desired spark at any time when the plug is energized.

However the resilient pallet 7 exists intermediate of the terminal 10 and the extension 6, and, being susceptible of swinging motion, will intermittently engage the terminal 10 by said reciprocal motion which will be produced by the action of the intake of the cylinder, it being understood that the plug is to be so positioned when screwed into the cylinder head that the pallet stands transversely in respect to a line intermediate of the intake valve and the cylinder so that each time the rush of gas occurs to the cylinder it will forcibly actuate the pallet and cause it to scrape against the end 12 of the terminal 10, but said action will be limited by the extremev end of the terminal 10 abutting the upper edge of the step or lug 9 on the pallet previously described By this arrangement it is seen that the constant engaging with slight scraping motion of the pallet and the terminal 10 will tend to insure positive cleanliness of the sparking gap.

For convenience in placing the plug in the proper position in the cylinder, I prefer to provide the upper face of the body portion thereof with arrows indicated at 13 which point in a direction. at right angles to the face of the pallet T and which arrows should point approximately towards the intake for best results. i 7

Having thus described my invention, what I claim and desire to secure by Letters Patentis: p

A spark plug having electrodes whose termini are spaced apart laterally from each other, a resilient member rigidly fixed at one end to one of the electrodes for alternate engagement with the termini of the electrodes.

In testimony whereof I hereunto my signature in the presence of two witnesses.

EARL T. MARTIN;

Witnesses:

S. C. BRoNsoN, S. Gno. STEVENS. 

